Hello, it's been a long time since I've been on here, well anyway
My little brother has a kfx 400 that he's had for a few months now and recently it's starting to get hard to start, not a weak battery or a fuel issue which makes us think it's the valves getting out of whack. And he also says it just falls on it's face in second gear, like there is no power in that year but all other gears are fine, I think this might be the gears on it but it would have always been like that, and I wouldn't think that the valves would affect just one gear